Re: Clarifying the 'padding alist-key

[Alexander Kobel]

On 2010-12-09 16:15, Mark Polesky wrote:
> Mark Polesky wrote:
> > 1)
> > padding - the minimum required amount of vertical
> > whitespace between two items, measured in staff-spaces.
> > When available, skylines are used in the spacing
> > calculation.
> >
> > 2)
> > padding - the minimum required amount of vertical
> > whitespace between the skylines of two items, measured in
> > staff-spaces.
>
>
> Carl Sorensen wrote:
> > I prefer 2.
>
> Trevor Daniels wrote:
> > 2, but is "skylines" explained anywhere in the docs?  If
> > it is, it is not indexed.

2 for me, too.

> Interesting.  I just assumed you'd both prefer #1, because
> IIUC most items don't have skylines for padding.

Most?  Anyway, after all, the main task of LilyPond still is typesetting 
/music/, not the headers.  And for the spacing of staves, the skyline is 
both available and essential to understand, and should be prominently 
advertized.

> For example, do things like title/toplevel markups, lyrics, etc.
> have skylines?

Markups: No, but - no skyline is a skyline, too, just a flat one...  I 
consider this as a missing feature; I don't see the point why headers 
and toplevel markups should not have skylines.  It's an annoyance when a 
single high note and a tempo mark at the beginning of a piece push the 
distance to the header, although only the composer and arranger (right 
side markup) are given.  So, documenting the skylines sounds like the 
correct thing to me, but stating that top-level markup's ones are, well, 
somewhat unusual for now.
("When available" from #1 sounds simple and descriptive, though, but I'd 
like to have skyline the default.)

Lyrics do have skylines, as well as chord names and IIUC basically 
everything you can enter in a score block.  That is, everything /but/ 
top-level markups?
(Though sometimes the estimations aren't that good as well; see the 
discussions recurring every now and then about refining skylines for 
hairpins, slurs or volta brackets, where the skylines are used for the 
intra-system spacing and extent estimation.)

> Trevor: when I `git grep' for "skyline" in the Documentation
> directory, I get nothing, so to answer your question: no,
> skylines are not explained anywhere in the docs.

Well, the same point I mentioned in 
<http://codereview.appspot.com/2316042/>, right?
I'm still not sure if it eases or complicates things to not use the term 
for the user, but in the end it's not too hard to understand to spare it 
out.  And that it's lacking in the whole Documentation dir means that 
it's in absolutely no docs, right?  That's bad - I can't see a point 
where this fits in the IR, but for some spacing tweaks it's important to 
have the real deal explained.


Cheers,
Alexander